Radiation

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In physics, radiation describes any process in which energy emitted by one body travels through a medium or through space, ultimately to be absorbed by another body. Non-physicists often associate the word with ionizing radiation (e.g., as occurring in nuclear weapons, nuclear reactors, and radioactive substances), but it can also refer to electromagnetic radiation (i.e., radio waves, infrared light, visible light, ultraviolet light, and X-rays) which can also be ionizing radiation, to acoustic radiation, or to other more obscure processes. What makes it radiation is that the energy radiates (i.e., it travels outward in straight lines in all directions) from the source. This geometry naturally leads to a system of measurements and physical units that are equally applicable to all types of radiation.

For more information about Radiation, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with radiation

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Touchable hologram

Touchable Hologram Becomes Reality (w/ Video)

Technology / Hi Tech

created Aug 06, 2009 | popularity 4.6 / 5 (51) | comments 18

(PhysOrg.com) -- Researchers from the University of Tokyo have developed 3D holograms that can be touched with bare hands. Generally, holograms can't be felt because they're made only of light. But the new ...


Physicists Demonstrate Quantum Memory with Matter Qubits

Physicists Demonstrate Quantum Memory with Matter Qubits

Physics / Quantum Physics

created Jul 03, 2009 | popularity 4.3 / 5 (21) | comments 2

(PhysOrg.com) -- For the first time, scientists have successfully operated a quantum gate between two remote particles of matter, marking an important step toward the development of a quantum computer. In ...


New Research Promises Better Atomic Clocks

Physics / General Physics

created Apr 22, 2009 | popularity 4.7 / 5 (9) | comments 1

(PhysOrg.com) -- The most accurate timekeepers in the world are atomic clocks, which tell time based on the absorption of a very specific and unchanging microwave frequency, which induces electrons in an atom to “jump” from ...


Supervolcano eruption -- in Sumatra -- deforested India 73,000 years ago

Supervolcano eruption -- in Sumatra -- deforested India 73,000 years ago

Space & Earth / Earth Sciences

created Nov 23, 2009 | popularity 4.5 / 5 (17) | comments 3

A new study provides "incontrovertible evidence" that the volcanic super-eruption of Toba on the island of Sumatra about 73,000 years ago deforested much of central India, some 3,000 miles from the epicenter, ...


Scientists Reproduce a Building Block of Life in Laboratory

Scientists Reproduce a Building Block of Life in Laboratory

Chemistry / Biochemistry

created Nov 06, 2009 | popularity 4.9 / 5 (28) | comments 0

(PhysOrg.com) -- NASA scientists studying the origin of life have reproduced uracil, a key component of our hereditary material, in the laboratory.


Hidden Territory on Mercury Revealed

Hidden Territory on Mercury Revealed

Space & Earth / Space Exploration

created Nov 04, 2009 | popularity 4.8 / 5 (20) | comments 1

The MESSENGER spacecraft's third flyby of the planet Mercury has given scientists, for the first time, an almost complete view of the planet's surface and revealed some dramatic changes in Mercury's comet-like ...


Gamma-ray photon race ends in dead heat; Einstein wins this round

Gamma-ray photon race ends in dead heat; Einstein wins this round

Physics / General Physics

created Oct 28, 2009 | popularity 4.7 / 5 (35) | comments 62

Racing across the universe for the last 7.3 billion years, two gamma-ray photons arrived at NASA's orbiting Fermi Gamma-ray Space Telescope within nine-tenths of a second of one another. The dead-heat finish ...


A woman dials a cell phone in her car

WHO study suggests link between cell phones and tumors

Medicine & Health / Cancer

created Oct 27, 2009 | popularity 4.2 / 5 (23) | comments 17

(PhysOrg.com) -- Preliminary results of an International investigation by the World Health Organization (WHO) suggest there may be a "significantly increased risk" of some types of brain tumors after use of ...


Physicists Turn to Radio Dial for Finer Atomic Matchmaking

Physicists Turn to Radio Dial for Finer Atomic Matchmaking

Physics / General Physics

created Oct 20, 2009 | popularity 4.5 / 5 (4) | comments 1

(PhysOrg.com) -- Investigating mysterious data in ultracold gases of rubidium atoms, scientists at the Joint Quantum Institute of the National Institute of Standards and Technology and the University of Maryland ...


UNH space scientists help catch the interstellar wind

Scientists Explore Galactic Frontier, Release First-Ever All-Sky Map (w/ Video)

Space & Earth / Space Exploration

created Oct 15, 2009 | popularity 4.8 / 5 (23) | comments 2

(PhysOrg.com) -- NASA's Interstellar Boundary Explorer, or IBEX, spacecraft has made it possible for scientists to construct the first comprehensive sky map of our solar system and its location in the Milky ...


To peer inside a living cell

To peer inside a living cell

Physics / General Physics

created Oct 06, 2009 | popularity 5 / 5 (11) | comments 3

(PhysOrg.com) -- Quantum mechanics could help build ultra-high-resolution electron microscopes that won't destroy living cells, according to MIT electrical engineers.


Heart of a galaxy emits gamma rays

Heart of a galaxy emits gamma rays

Space & Earth / Astronomy

created Oct 02, 2009 | popularity 4.5 / 5 (6) | comments 6

(PhysOrg.com) -- Quite a few distant galaxies turn out to be cosmic delivery rooms. Large numbers of massive stars are born in the hearts of these starburst galaxies, and later explode as supernovae. In the ...


Very High Energy Gamma Rays

Very High Energy Gamma Rays

Space & Earth / Astronomy

created Sep 25, 2009 | popularity 4.7 / 5 (10) | comments 3

(PhysOrg.com) -- Gamma-rays are the most energetic known form of electromagnetic radiation, with each gamma ray being at least one hundred thousand times more energetic than an optical light photon. The most ...


Solar cycle driven by more than sunspots; Sun also bombards earth with high-speed streams of wind

Solar Cycle Driven by More than Sunspots

Space & Earth / Space Exploration

created Sep 17, 2009 | popularity 4.2 / 5 (14) | comments 4

(PhysOrg.com) -- Challenging conventional wisdom, new research finds that the number of sunspots provides an incomplete measure of changes in the Sun's impact on Earth over the course of the 11-year solar ...


Planck first light yields promising results

Planck first light yields promising results (w/ Video)

Space & Earth / Space Exploration

created Sep 17, 2009 | popularity 4.8 / 5 (11) | comments 0

(PhysOrg.com) -- Planck, ESA's mission to study the early Universe, started surveying the sky regularly from its vantage point at L2 on 13 August. The instruments of ESA's 'time machine' were fine-tuned for ...